Vehicles are equipped with various monitoring and security systems. These systems include tire pressure monitoring (TPM) systems and remote keyless entry (RKE) systems. A conventional tire pressure monitoring system is configured to monitor a parameter (e.g., tire pressure) of the vehicle's wheels. The RKE system enables a user to remotely lock and unlock the vehicle's doors. Conventional RKE systems are responsive to a key fob having buttons that cause the generation of signals that enable the activation of various vehicle systems such as a vehicle's door locking system, alarm system, and the like. Recently, passive entry systems have been integrated with vehicles, wherein a vehicle operator may lock and unlock his/her doors without pressing a button on a key fob. For example, with the passive entry systems, the vehicle operator may unlock the vehicle by simply placing the fob within a certain proximity of the vehicle. As such, the vehicle operator is not required to press buttons to activate vehicle systems or functions.
As described above, TPM, RKE, and passive entry systems enable the generation of signals for invoking various vehicle functions. These signals are received at a receiver. Although the conventional receiver is capable of receiving the TPM, RKE, and passive entry signals, there exists a wide horizon for improvement. In particular, there are many instances where, for example, the TPM signal and the passive entry signal are transmitted simultaneously. Additionally, these transmitted signals are conventionally transmitted at frequencies that result in signal interference, thereby causing the receiver to not receive the TPM signal and the passive entry signal. The same is true with RKE signals, which may be transmitted at the same frequencies and simultaneously with the TPM signals and/or the passive entry signals.
The present invention was conceived in view of these and other disadvantages of conventional TPM, RKE, and passive entry receivers.